The secret of a long and healthy life is in these hills. Maria Pio Fusi looks out over the olive groves and vines owned by her son in Italy’s Chianti region of Tuscany, and smiles.

“Our doctors tell us to drink a little wine every day, one or two glasses for our health,” she says, as a pensioner in a place where life expectancy is among the highest in Europe. “Wine is the secret of life.”

Scientists have agreed with this for the past 20 years, and even identified a miracle ingredient in red wine that makes people healthier. But new research says resveratrol, as it is called, actually has no effect.

“Red wine will not make you live longer,” screamed one headline, only months after different scientists said it could help us live to 150.

So which is true? Is red wine good for you or not?

Fusi’s son owns a vineyard the market town of Greve. The local olive oil is famously pure. The meat is wonderful. There are black and white truffles to be savoured. Small wonder that researchers came here to study the drinking habits and health of the older folk.

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In 1998, they took urine samples from 783 men and women over age 65 in this town and a nearby village and examined them for levels of resveratrol — one of the natural chemicals found in the skin of the red grape and an antioxidant, which neutralizes the oxygen molecules that damage human cells. The claims made for resveratrol have become increasingly bold in recent years, including that it can boost memory, arrest the failure of eyesight and hearing, lower cholesterol, restore muscle strength, reduce the signs of aging and even prolong life.

‘The levels of resveratrol in many red wines are often undetectable’

But these claims are based on tests with mice, not people. The team led by Richard Semba of Johns Hopkins University wanted to see the effects on humans, so they compared the urine samples with the results of a detailed health survey the same pensioners took three times in nine years. They expected those with more resveratrol to live longer and be less likely to suffer from cancer or heart disease.

“We were expecting a connection because that is what you hear,” says Semba. “But in retrospect, it was a leap of faith to go from tests on mice and cellular models to expect an effect like this in humans. It was a complete wash, actually. There was no association.”

Robert Corder, professor of experimental therapeutics at Queen Mary, University of London, is not surprised by the new research. “The levels of resveratrol in many red wines are often undetectable and negligible. It’s frustrating that everybody has been misled for so long.”

Corder is the author of The Red Wine Diet, but the title is misleading. “I am a big fan of wine, but I strongly advocate that you should drink less, of better quality.”

He insists that the pips and not the skins of the grapes are the source of good health. They release compounds called flavonols, which evolve into molecules that improve blood pressure and blood flow and are also antioxidants.

Unfortunately, to get any benefit you need to drink wines fermented longer using traditional techniques and that are rich in tannins, and therefore a little harsh for many tastes: “Your average [cheap] wine does not have enough flavonols in it to confer any kind of health benefit,” Corder says.

‘Over-consumption of alcohol of any type is universally associated with increased blood pressure, increased risk of stroke and of cancer’

The other problem is that some people have become so convinced red wine is medicinal that they drink too much.

“There’s a lot of people who think half a bottle of wine a day is a healthy amount,” says Corder. “It isn’t. Over-consumption of alcohol of any type is universally associated with increased blood pressure, increased risk of stroke and of cancer.”

But what about the Italians? They drink far more wine than Canadians — 37.63 litres a year to 15 litres annually in Canada — and they also live longer. World Health Organization statistics from last year say Canadian life expectancy is 82.5 years, 83.1 for Italians.

‘If you have one or two small glasses at lunchtime, the alcohol has cleared your system without reaching levels that do harm’

The answer is Italians drink a little every day, rather than saving it all up for a binge weekend, Corder says.

“If you have one or two small glasses at lunchtime, the alcohol has cleared your system without reaching levels that do harm, before you have the same in the evening,” Corder says.

“If you try to put the same amount down you immediately after work with no food … then the consequence is a very high level of alcohol in the blood, which is when you start to modify proteins and DNA and raise your blood pressure.”